Pierre Levet's editio princeps
of Villon's works, a gothic type face incunable, published in 1489. In
editing tradition, "I" also stands for Levet's manuscript source(s). It
contains the following
works by Villon:

Peckham, Robert D. François
Villon: A Bibliography, Garland Medieval Bibliographies, 3. New
York & London: Garland Publishers, Inc., 1990, 7-27 [for
the number of official textual sources described (manuascripts and
early printed editions), the most comprehensive resource in print].